Improvement in bark-cutting machines



v 2Sheets-Sheet 1 S. R. THOMPSON.

Bark-CuttvngMaohine.

No. 200,361. y' Pafente.d.Feb.-12,1s7s.

N. PETERS. PHUTOL|THOGRAPHR, WASHINGTON, D C,

2 Sheets-Sheet 2 s. R. THOMPSON. Bark-Cutting Machine. Ne. 200,361.

Patented Feb. 12, 187s.

N. PETERS, PHOTD-LITHOGRAPMER. WASHINGTON. D

UNITnn STATES PATENT SAMUEL R. THOMPSON, OF BROOKLINE, MASSACHUSETTS.

VtIMPROVQEIVISENT IN BARKECUTTI'NG MACHINES.

Specication forming part of Letters Patent No. 200,361, dated February 12, 1878; application-'filed January 26, 1878. Y

To all whom )it may concern Be it known that I, SAMUEL R. THOMPSON, of Brookline, in the State of Massachusetts, have invented certain lmprovements in Bark- Cutting Machines, of which the following is a specification This invention is an improvement on the bark-cutting machine' for which Letters Patent No. 176,907 Were granted to me April 25,'

The present invention consists in certain improvements looking to the more perfect op-1 eration `of the machine incuttin g or -reducing bark to particles, all of which are duly setI forth and claimed hereinafter.

In the drawings, Figure 1 represents a side 9 represents a transverse-vertical section of the machine, showing an vendless feeding-beltI applied to the bed-plate. Fig. V10 representsf a side view of the Afeed-roll without its teeth,

- ter forces the .,coarser yparticles toward the showing its bearing-blocks in section.

Similar letters of referenceindicate corre-Q by the teeth al, 1thespace between lthe 4shoulder ml'and the points of the 'teeth being such spending parts. A represents the rotary kcutter which reduces or rosses the bark. M represents the adjustable bed-plate which -supports the barkl as it passes tothe cutter. E represents the ad- `)ustable feed-roll which feeds the bark to the cutter, and is located on hinged arms vF,so

as yto rise and fall and -D represents theback plate, which is located behind the cutter, these parts being in construction andoperation, excepting in certain hereinafter-meuf tioned particulars, like the corresponding parts 1n my before-mentioned patent, to which reference is made for a full description. The cutter A is provided with isolated teeth al, as in my previous patent, and -is journaled in -blo'cks or lbearings located on the side pieces B -B of the supporting-frame, the teeth a1,-when revolving, coming in close proximity to a shoulder, m, in which the bed-plate M terminates, and detachin g Vfragments of bark from a sheet .supportedon said bed-plate.

C represents al concave formed as a sieve or perforated partition, which is located under the cutter A, and entirely fills the space provided for the descent-of the particles of bark ifrom the cutters to the `receptacle or-chut'e below. The sieve C is composed of -a perforated plate-or yof wire, yas preferred, the openfings therein being no larger than is necessary l@to permit the rpassage through them of particles of bark of the maximum sizedesired'for lleaching, so that llarger or coarser 'particles Will be arrested. The sieve is parallel with ith'e cutter A -'longitudinally, and Ais lcurved transversely, and is preferably arranged soA lthat its rear edge is nearer the cutter than its ifrontedge, a space, c, being thus formed beftween the sieve and the cutter A, which space converges from the front lto `the rear" side of the cutter, as shown -in Figs. 3 and 5. The rearedge of the `sieve C yforms a shoulder, m1, which is in close proximity to the teeth of the cutter. i

'It will be seen that as the particlesof bark are cut by the teeth a they fall onto the sieve fC, so that the particles of the desired size pass- Ithrough the sieve, while the coarser particles are arrested thereby. The rotation of the cutshoulder m1, where they are arrested and cut up that the particles arrested by the sieve-cannot pass between the shoulder and the cutter until reduced to a smallersize. Hence all-the bark is reduced toa conditionofuniform tneness before it leaves the machine. The rotation'of the cutter forces the particlesof bark agaiustthe converging or inclined 4surface of the sieve, and thus crowds or forces the Vprop:- erly-reduced fragments through the sieve, so that the vlatter is not liable tobecome clogged.

Incutting bark 'and preparing it for leachf in-g it is very important that the bark lshould be reduced to particles lof as near a uniform size as possible. The particles shouldneither be inthe form of coarse lumps norof dust or powder, asin the Vlatter condition it forms in masses, which 'float on Vthe surface 'and resist the action of the water, and in neither conditionis its full value readily extracted by the leaching process.

By the above-described combination, viz., the rotary cutter having isolated cutting-teeth, and the sieve or perforated partition, I avoid the formation of powder to a great extent, and the presence of coarse lumps in the reduced bark, the lumps which may be broken down by the cutter from the bark resting on the bed-plate being arrested by the sieve and cut up by the rteeth of the cutter without any considerable percentage being crushed into powder.

The sieve and cutter may be employed to equalize the particles of bark which have been cut in another machine, in which case the bedplate M and its shoulder m will not be required, and the cut bark will be introduced into the space c by any suitable means.

The shoulder m1 on the sieve C need not project inwardly toward the cutter, as shown, as the edge of the sieve C, arranged at a proper distance from the cutter, will form a sufficient shoulder. y

F represents a hood or cover, which is attached to the bed-plate M, and is arranged to cover the cutter A and feed-roll E, as shown. I prefer to bolt the sides of the hood or cover to the side pieces png of the bed-plate, as shown in Figs. l and 3. The rear edge of the cover is bolted, preferably, to a 'gate or partition, G, which is located on the back plate D. These parts-viz., the hood F, the gate G, and the side pieces naform a close casing over and around the cutter and the feed-roll, which prevents the particles of bark from being scattered by the cutter, and causes the particles which are thrown upwardly by the cutter to return to the space c, to be forced through the sieve. The front portion of the hood or coveris operi, as shown at b, for the admission of bark. The sides of the hood or cover are provided with slots d', through which the journals of the.l feed-roll pass, and in which said journals rise and fall. I represents an extension, which is hinged to the bed-plate M, and isA adapted to be inclined at any desired degree, an extensible leg, I', being provided to support the extension. z' t' represent side pieces with which the extension I is provided. When the extension I is inclined upwardly, as shown in Figs. l and 3, it facilitates the passage of the bark to the cutter, both when the bark is presented in large sheets or in small fragments. Vhen the sheets of bark are to be rossed, and are warped or curved` longitudinally, the extension may be inclined downwardly, so that the central portion of the sheet of bark will not project too far above the bed-plate, the bark being presented with its concave inner side down. The gate or partition Gr is located in guides or holders G on the back plate, and is removable from said holder, so that, when the machine is used for rossing, the ross will pass over the back plate. I prefer to provide the guides with catches or buttons g, adapted to engage with lugs or projections g on the partition Gand hold said partition down against the back plate D, or raised and separated from said back plate.

If desired, the bed-plate M may be extended outwardly, and provided with an en dless apron, K, running on rolls K', which are journaled in the bed-plate, as shown in Fig. 9, and are positively rotated by any desired means, so as to cause the apron K to convey bark toward the cutter A. Thefeed-roll E is journaled in bearing-blocks El El, which are located on the independently-pivoted arms F F as shown in my aforesaid patent.

7When the bark passing under the feed-roll varies in thickness transversely, the roll E is liable to be inclined longitudinally one of its.

ends being raised independently to facilitate the inclination of the roll E. I provide the block E1 with double conical sockets E2, arranged to give the journals of the roll E a steady bearing, and prevent them from Wabbling, and at the same time permit the roll to be inclined, as shown in dotted lines in Fig.`

lIn my before-named patent the cutter A was composed of a series of disks or collars, each having two or more teeth formed on yits periphery, the collars being arranged on a rod or mandrel.

I now construct the cutter as follows: A

represents a cylinder, lwhich composes the' body of the cutter, and is suitably provided l teeth, so that the latter can be readily inserted and removed. The bars a areadapted to be removed from the grooves g, and arel held therein by any suitable means. I prefer to make the grooves g and bars e in dovetail form, as shown in Fig. 5, so that the bars cannot be removed outwardly; and to hold the bars longitudinally I prefer to provide the cylinder, at its end, with detachable caps a2,

a3, these being provided preferablywith inwardly-projecting flanges a4, as shown in Fig. 6, and screwed or otherwise affixed to the journals of cylinder A. The flanges a4 project over the ends of the bars a. Iprovide the cap c3 with a recess, a5, adapted to register with one of the grooves g when the cap is properly turned, as shown in Fig. 7, to permit the longitudinal movement of the bar in that groove. The cap a3 may be turned to cause the recess a5 to register with any of the l groovesg. I prefer to provide a jam-nut, a6,

to hold the cap a3.

` By the described construction I am enabled to readily remove a broken tooth and supply.A

its place with a new one,and, as each tooth is independent, it will be seen that it will be an easy and inexpensive matter to replace a broken one.

I do not limit myself to the precise details of construction of the cutter, as any suitable means for securing the rods or bars a and their teeth al may be employed without departing from the spirit of my invention.

I claim as my invention- 1. The combination of a rotary cutter, having isolated cutting-teeth, and a converging concave, formed as a sieve or perforated partition, whereby the larger particles or lumps of bark between the cutter and concave are separated from the smaller particles, and subjected to the action of the cutter, to be cut up thereby Without crushing, and the smaller particles impelled through the sieve.

2. Inka bark-cuttin g machine, the combination of a rotary cutter, A, a bed-plate, M, having a shoulder, m, and a curved sieve or perforated partition, C, arranged to form alaterally-converging space under said cutter, and terminating in a shoulder, m1, all arranged substantially as and for the purpose specified.

3. In a bark-cutting machine employing a rotary cutter, A, and a rising and falling feedroll, E, a hood or casing, F, supported on the bed of the machine, arranged to cover the eutter and feed-roll, and provided with slots d', in which the journals of the feed-roll may rise and fall, substantially as described.

4. The feed-roll E, combined with theblocks El, adapted to rise and fall independently, and provided with the double conical bearings E2, substantially as and for the purpose specified.

5. The rotary cutter A, composed of the longitudinallygrooved cylinder or body A' and the detachable rods or blocks c, each provided with a series of detachable teeth, al, substantially as described.

6. The combination of the grooved cylinder or body A', the rods or blocks a, having teeth al, and means, substantially as described, for securing the blocks in the cylinder.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses. e

SAMUEL It. THOMPSON.

Witnesses:

G. F. BROWN, GEORGE W. PIERCE. 

